An alarm screen comprises a frame comprising a laser sensor, a processing unit, and a wireless transmitter embedded in a hollow interior. The frame comprises an opening for the laser sensor to project a laser beam outside of the alarm screen. The laser sensor projects the beam through the opening, makes a set of one or more measurements of a distance between the laser sensor and an object in a path of the laser beam, and sends the set of measurements to the processing unit. The processing unit is configured to compare the distance measurements received from the laser sensor with a threshold distance detect, and send one or more signals to the wireless transmitter when at least one of the distance measurements received from the laser sensor exceeds the threshold. The wireless transmitter is configured to receive signals from the processing unit and wirelessly transmit the signals.

A system includes an optical fiber provided in a monitor area, a detection unit that monitors the monitor area, a monitor, and a control unit that displays a monitoring situation of the monitor area on the monitor. The detection unit detects an anomaly that has occurred in the monitor area and identifies a location on the optical fiber where the anomaly is detected, based on a vibration pattern included in an optical signal received from the optical fiber. On the monitor, as a monitoring situation of the monitor area, the control unit displays an arrangement situation of the optical fiber in an overlapping manner on a map of the monitor area, displays a mark indicating a location on the optical fiber where the anomaly is detected, in an overlapping manner on the map of the monitor area, and displays information indicating a detail of the anomaly.

The application provides a interface light path structure with all polarization-maintaining function. A first polarization-maintaining-transferring device includes a first port, a second port, and a third port, wherein the first port receives a first polarized light output by the polarization beam-splitting device, the second port is connected to the first Faraday rotation mirror, and the third port is connected to a first port of the first polarization-maintaining coupler. A second polarization-maintaining-transferring device includes a first port, a second port, and a third port, wherein the first port receives a second polarized light output by the polarization beam-splitting device, the second port is connected to the second Faraday rotation mirror, and the third port is connected to a second port of the first polarization-maintaining coupler.

An optical fiber sensing system according to the present disclosure includes a receiving unit (21) configured to receive an optical signal from an optical fiber (10) for sensing, an identifying unit (22) configured to identify an occurrence of an event and a type of the event that has occurred based on a vibration pattern included in the optical signal, an acquiring unit (23) configured to acquire a detection condition pertaining to a period corresponding to the type of the event identified by the identifying unit (22), and a determining unit (24) configured to determine that the event identified by the identifying unit (22) is an anomaly if the detection condition is satisfied.

A detection system according to the present disclosure includes an optical fiber (10X, 10Y) laid in a portable base station area (45) in which a portable base station (40) is installed, a reception unit (20) receiving an optical signal from the optical fiber (10X, 10Y), the optical signal containing information indicating a state of the portable base station area (45), and a detection unit (32) detecting a threat in the portable base station area (45), based on the information indicating a state of the portable base station area (45) being contained in the optical signal.

In an optical fiber monitoring system which detects physical disturbance or other parameters such as temperature or strain of a fiber where a monitor signal is transmitted along the optical fiber and analyzed to detect changes which are indicative of an event, a method is provided for periodically checking proper operation of the optical fiber monitoring system. A fiber disturbance actuator periodically causes a pattern of disturbances of a portion of the fiber at a predetermined location thereon where the disturbance is characteristic of the event to be monitored. The monitor signal is analyzed to detect the pattern of changes and in the event that expected changes are not detected, a warning is issued that the intrusion detection system is not properly operating.

The optical fiber sensing method according to the present disclosure includes: sensing optical fibers being redundantly laid (10A1, 10A2); an execution unit (22) that executes sensing with the sensing optical fibers (10A1, 10A2); a detection unit (23) that detects occurrence of a fault in the sensing optical fiber (10A1) of an active system among the sensing optical fibers (10A1, 10A2); and a switching unit (21) that performs switching in such a way that the execution unit (22) executes sensing with the sensing optical fiber (10A2) of a standby system among the sensing optical fibers (10A1, 10A2) when the detection unit (23) detects occurrence of a fault.

An image processing apparatus (40) according to the present disclosure includes a display unit (42) and a control unit (41) configured to control the display unit (42) to display a sensing data image indicating sensing data of an optical fiber and a camera image of a camera (50) which photographs an area in which a predetermined event is detected by the sensing data.

An alarm screen comprises a frame comprising a laser sensor, a processing unit, and a wireless transmitter embedded in a hollow interior. The frame comprises an opening for the laser sensor to project a laser beam outside of the alarm screen. The laser sensor projects the beam through the opening, makes a set of one or more measurements of a distance between the laser sensor and an object in a path of the laser beam, and sends the set of measurements to the processing unit. The processing unit is configured to compare the distance measurements received from the laser sensor with a threshold distance detect, and send one or more signals to the wireless transmitter when at least one of the distance measurements received from the laser sensor exceeds the threshold. The wireless transmitter is configured to receive signals from the processing unit and wirelessly transmit the signals.

An optical fiber sensing system according to this disclosure includes: a cable (20) including optical fibers; a reception unit (31) configured to receive, from at least one optical fiber included in the cable (20), an optical signal having a pattern in accordance with a state of a target to be monitored; and a monitoring unit (32) configured to specify the location of the target to be monitored based on the pattern that the optical signal has and specify the trajectory of the target to be monitored based on a locational variation of the specified location.